medium CVSS 5.5 EPSS <0.1%

CVE-2023-52703·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: net/usb: kalmia: Don't pass act_len in usb_bulk_msg error path syzbot reported that act_len in kalmia_send_init_packet() is uninitialized when passing it to the first usb_bulk_msg error path. Jiri Pirko noted that it's pointless to pass it in the error path, and that the value that would be printed in the second error path would be the value of act_len from the first call to usb_bulk_msg.[1] With this in mind, let's just not pass act_len to the usb_bulk_msg error paths. 1: https://lore.kernel.org/lkml/Y9pY61y1nwTuzMOa@nanopsycho/

Severity
medium
Software
Kernel
Fixed in
6.1.13
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — in the bottom 1% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Affected versions

From: 5.16

Until: 6.1.13

Fixed in: 6.1.13

How to fix this CVE

Update your Linux kernel to version 6.1.13 or later to address a flaw in the kalmia USB driver's error handling path. The vulnerability stems from uninitialized variable usage in error conditions that could lead to kernel crashes. Ensure all systems running kernel versions 5.16 through 6.1.12 are patched immediately.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check installed kernel version: uname -r (should be 6.1.13 or later)
  2. Verify kalmia USB driver is loaded: lsmod | grep kalmia
  3. Check dmesg for USB initialization errors: dmesg | grep -i 'kalmia\|usb.*error'
  4. Confirm kernel patch level: grep -i 'CONFIG_' /boot/config-$(uname -r) | grep -i usb

FAQ

What is CVE-2023-52703?

This is a medium-severity kernel vulnerability affecting the kalmia USB network driver, where uninitialized variable values could be referenced in error handling routines, potentially causing kernel availability issues.

Is CVE-2023-52703 being actively exploited?

No, this vulnerability is not listed in the CISA KEV catalog and has no known public exploits. However, it still requires patching due to its potential impact on system stability.

What versions of Kernel are affected by CVE-2023-52703?

Linux kernel versions 5.16 through 6.1.12 are vulnerable. The fix is included in kernel 6.1.13 and all subsequent releases.

How do I check if my server is vulnerable to CVE-2023-52703?

Run 'uname -r' and compare the version number. If it shows 5.16.x, 5.17.x, 5.18.x, 5.19.x, 6.0.x, 6.1.0 through 6.1.12, your system is vulnerable.

Does Defensia detect CVE-2023-52703?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2023-52703 will appear in your dashboard with remediation steps.

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References

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